C :

#include <stdio.h>
int main()
{
int a,b;
while(scanf("%d %d",&a, &b) != EOF)
printf("%d\n",a+b);
return 0;
}

C++ :

#include <iostream>
using namespace std;
int main() {
    int a,b;
    while (cin >> a >> b) {
        cout << a+b << endl;
    }
	return 0;
}

Java :

import java.util.*;
public class Main {
	public static void main(String args[]) {
		Scanner cin = new Scanner(System.in);
		int a, b;
		while (cin.hasNext()) {
			a = cin.nextInt(); 
			b = cin.nextInt();
			System.out.println(a + b);
		}
	}
}